feat(health): detect stale and orphan worktrees in validate-health (W017) (#2175)

Add W017 warning to cmdValidateHealth that detects linked git worktrees that are stale (older than 1 hour, likely from crashed agents) or orphaned (path no longer exists on disk). Parses git worktree list --porcelain output, skips the main worktree, and provides actionable fix suggestions. Gracefully degrades if git worktree is unavailable.

Closes #2167

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/orphan-worktree-detection.test.cjs

@@ -0,0 +1,126 @@
+/**
+ * GSD Tools Tests - Orphan/Stale Worktree Detection (W017)
+ *
+ * Tests for feat/worktree-health-w017-2167:
+ *   - W017 code exists in verify.cjs (structural)
+ *   - No false positives on projects without linked worktrees
+ *   - Adding the check does not regress baseline health status
+ */
+
+const { describe, test, beforeEach, afterEach } = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('fs');
+const path = require('path');
+const { runGsdTools, createTempGitProject, cleanup } = require('./helpers.cjs');
+
+// ─── Helpers ────────────────────────────────────────────────────────────────
+
+function writeMinimalProjectMd(tmpDir) {
+  const sections = ['## What This Is', '## Core Value', '## Requirements'];
+  const content = sections.map(s => `${s}\n\nContent here.\n`).join('\n');
+  fs.writeFileSync(
+    path.join(tmpDir, '.planning', 'PROJECT.md'),
+    `# Project\n\n${content}`
+  );
+}
+
+function writeMinimalRoadmap(tmpDir) {
+  fs.writeFileSync(
+    path.join(tmpDir, '.planning', 'ROADMAP.md'),
+    '# Roadmap\n\n### Phase 1: Setup\n'
+  );
+}
+
+function writeMinimalStateMd(tmpDir) {
+  fs.writeFileSync(
+    path.join(tmpDir, '.planning', 'STATE.md'),
+    '# Session State\n\n## Current Position\n\nPhase: 1\n'
+  );
+}
+
+function writeValidConfigJson(tmpDir) {
+  fs.writeFileSync(
+    path.join(tmpDir, '.planning', 'config.json'),
+    JSON.stringify({
+      model_profile: 'balanced',
+      commit_docs: true,
+      workflow: { nyquist_validation: true, ai_integration_phase: true },
+    }, null, 2)
+  );
+}
+
+function setupHealthyProject(tmpDir) {
+  writeMinimalProjectMd(tmpDir);
+  writeMinimalRoadmap(tmpDir);
+  writeMinimalStateMd(tmpDir);
+  writeValidConfigJson(tmpDir);
+  fs.mkdirSync(path.join(tmpDir, '.planning', 'phases', '01-setup'), { recursive: true });
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// 1. Structural: W017 code exists in verify.cjs
+// ─────────────────────────────────────────────────────────────────────────────
+
+describe('W017: structural presence', () => {
+  test('verify.cjs contains W017 warning code', () => {
+    const verifyPath = path.join(__dirname, '..', 'get-shit-done', 'bin', 'lib', 'verify.cjs');
+    const source = fs.readFileSync(verifyPath, 'utf-8');
+    assert.ok(source.includes("'W017'"), 'verify.cjs should contain W017 warning code');
+  });
+
+  test('verify.cjs contains worktree list --porcelain invocation', () => {
+    const verifyPath = path.join(__dirname, '..', 'get-shit-done', 'bin', 'lib', 'verify.cjs');
+    const source = fs.readFileSync(verifyPath, 'utf-8');
+    assert.ok(
+      source.includes('worktree') && source.includes('--porcelain'),
+      'verify.cjs should invoke git worktree list --porcelain'
+    );
+  });
+});
+
+// ─────────────────────────────────────────────────────────────────────────────
+// 2. No worktrees = no W017
+// ─────────────────────────────────────────────────────────────────────────────
+
+describe('W017: no false positives', () => {
+  let tmpDir;
+
+  beforeEach(() => {
+    tmpDir = createTempGitProject();
+    setupHealthyProject(tmpDir);
+  });
+
+  afterEach(() => cleanup(tmpDir));
+
+  test('no W017 when project has no linked worktrees', () => {
+    const result = runGsdTools('validate health --raw', tmpDir);
+    assert.ok(result.success, `validate health should succeed: ${result.error || ''}`);
+    const parsed = JSON.parse(result.output);
+
+    // Collect all warning codes
+    const warningCodes = (parsed.warnings || []).map(w => w.code);
+    assert.ok(!warningCodes.includes('W017'), `W017 should not fire when no linked worktrees exist, got warnings: ${JSON.stringify(warningCodes)}`);
+  });
+});
+
+// ─────────────────────────────────────────────────────────────────────────────
+// 3. Clean project still reports healthy
+// ─────────────────────────────────────────────────────────────────────────────
+
+describe('W017: no regression on healthy projects', () => {
+  let tmpDir;
+
+  beforeEach(() => {
+    tmpDir = createTempGitProject();
+    setupHealthyProject(tmpDir);
+  });
+
+  afterEach(() => cleanup(tmpDir));
+
+  test('validate health still reports healthy on a clean project', () => {
+    const result = runGsdTools('validate health --raw', tmpDir);
+    assert.ok(result.success, `validate health should succeed: ${result.error || ''}`);
+    const parsed = JSON.parse(result.output);
+    assert.equal(parsed.status, 'healthy', `Expected healthy status, got ${parsed.status}. Errors: ${JSON.stringify(parsed.errors)}. Warnings: ${JSON.stringify(parsed.warnings)}`);
+  });
+});